Field of the Invention
The present invention relates to a coil component having a so-called drum core.
Description of the Related Art
There is a type of coil component referred to as the drum coil component, which has a drum core made of magnetic material, etc., and a coil formed by winding an insulating sheath conductor around the core. Mobile devices and other electronic devices of higher performance are required, which gives rise to a need for supplying high-performance components. Coil components are increasingly used in applications requiring high saturated current, and coil components of high withstand voltage are also in demand. In light of the above, there is a need for coil components that offer both high insulation property and high current characteristics.
According to the art described in Patent Literature 1, a coil component is provided by combining a ferrite core with an outer sheath containing ferrite powder, to achieve high inductance. Such coil component uses sintered ferrite powder, but such sintered powder maintains large specific surface area regardless of how it is produced, such as sintering a magnetic substance in powder form or crushing a sintered magnetic substance, and because a kneaded mixture of sintered powder and resin cannot have low viscosity, and for other reasons, the fill ratio of sintered powder needs to stay low. As a result, efforts have been made to achieve high inductance by making the outer sheath thicker and thereby achieving high shielding effect.
Any discussion of problems and solutions involved in the related art has been included in this disclosure solely for the purposes of providing a context for the present invention, and should not be taken as an admission that any or all of the discussion were known at the time the invention was made.